Cloning and sequencing of a Bordetella pertussis serum resistance locus.

摘要: We have characterized a new virulence factor in Bordetella pertussis: serum resistance. Compared with Escherichia coli HB101, wild-type B. pertussis was relatively resistant to classical-pathway, complement-dependent killing by normal human serum. However, mutant of (BPM2041) which is less virulent mice and has Tn5 lac inserted previously uncharacterized bvg-regulated gene found be at least 10-fold more susceptible than the wild type. named this locus brk, for resistance killing. cloned sequenced brk locus, it encodes two divergently transcribed open reading frames (ORFs), termed BrkA BrkB. Both ORFs are necessary Within 300 bases separate upstream each ORF putative sites BvgA binding. shows 29% identity pertactin RGD motifs addition conserved proteolytic processing site an outer membrane targeting signal. Like pertactin, involved adherence invasion. Despite similarities, not as sensitive or BrkB mutants. similar E. Mycobacterium leprae displays domains homology various transporters. On basis its hydropathy profile, predicted cytoplasmic protein. By Southern blot, sequences were bronchiseptica parapertussis but avium.